Method of protecting matrices.



s'rarns PATENT ormcn.

HUGO COHN, 0F GfiRLITZ, GERMANY.

METHOD OF PROTECTING MATRICES.

949,819. No Drawing.

I Specification of Letters Patent.

Application filed October 27, 1908. Serial No.

Patented Feb. 22, 1910. 459,786.

To all whom it may concern: I

Be it known that I, HUGO Conn, subject of the King of Prussia, residing at 19/20 Blumenstrasse, Gorlitz, in the Kingdom of Prussia and Empire of Germany, have invented new and useful Im rovements in Methods of Protecting Matrlces, of which the following is a specification.

The known flexible matrices used for casting the stereotype printing plates are ordinarily coated on their face with a protecting layer, so as to prevent the liquid metal from penetrating into the finest pores of the paper material and adhering to the latter, so that the matrices are protected from rapid destruction. Hitherto this protecting layer was made from mineral colors, which were applied in watery suspense. Such protecting layers, however, are-not suificiently tight and do not present a sufliciently uniformly metal forced by casting apparatus into the casting chamber from penetrating through the fine fissures and adhering to the fibers thereunder. The consequence of this is, that the flexible matrix can be unwound from the cast plate only with difficulties, so that it is easily destroyed. Moreover all the known protecting layers used in the paper manufacture present the defect, that on coming in.

-' contact with the liquid metal they gradually lose their smooth surfaces by forming bubbles, .broiling, twisting, loosening etc., so that they facilitate the adhering of the metal to the matrix. a

My invention relates to a method of protecting the matrix from the penetration and adhesion of the liquid metal during the casting of the stereotype printing plates, so that the matrix is rendered so durable as to be capable of withstandin almost an unlimited number of castings and to satisfy the severe requirements in the employment of casting apparatus, even at the maximum pressure of the liquid metal.

My method is as follows: The matrix is on its face first coated with any of the known mineral protecting materials uch as talcum, china clay, alum, borax, etc. and then, before the coat has completely dried, it is covered with a mass which contains aneasily fusible fat in a powdery condition. Instead of the above, however, it is preferable to use'the adhesive-substance known under the term of collodin, which is a vegetable gluey preparation made from starch, for forming the trix, which layer presentsthe advantages,

that even at the temperature of the liquid metal it does not change, but remains tight, anddoes not get off or loosen, neither in the heat nor in the cold. The fatty substance is preferably stearin in its finest powdery conition and with this stearin the matrix is powdered, so that the stearin is uniformly istributed over the matrix. The matrix is impressed with the respective type matter as usual and is then dried, z. e. heated, so that the stearin will melt and form a continuous thin fatty layer on the face of the matrix. The finished matrix is-before its insertion'in the casting apparatus preferably once more powdered with stearin by means of a soft brush. I recommend to repeat this powdering operation after every fourth or fifth. casting. During the casting operation the liquid metal enters the'casting chamber formed by the matrix and the stearin will melt.

The employment of stearin presents the special advanta e, thatit can be applied ma powdery con ition,.renders a rapid and uniform lubrication of the matrix possible and does not prevent the metal from exactly filling the spaces. The melted stearin 1s prevented by the coat under it from penetrating into the paper material of the matrix and it forms a protecting layer, whereby the coat itself is at the same time protected and the liquid metal is prevented from penetrating into the pores of the matrix.

I recommend to use the stearin powder in combination with talcum powder, because stearin alone is apt to form lumps. However, any other mmeral owder in place of talcum powder can be a ded to the stearin,

provided that this powder can be powdered and does not hinder the casting of the stereotype printing plates.

I claim:

1. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat, whereupon the latter is dried and, before being thoroughly dry, sprinkled with an easily fusible fat in powder form.

2-. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat, whereupon the latter is dried and, before being thoroughly dry, sprinkled with an easily fusible fat and with mineral substances in powder form.

3. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat, whereupon the latter is dried and, before being thoroughly dry, sprinkled with stearin powoer.

4. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat,

whereupon the latter is dried and, before being thoroughly dry, sprinkled with a mixture of stearinand talcum-powder.

5. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat of liquid starch aste, whereupon the latter is dried and, before being thoroughly dry, sprinkled with an easily fusible fat in powder form. v

'6. A process for protectingstereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat of liquid starch paste, whereupon the latter is dried and, before being thoroughly dry, sprinkled with a mixture of easily fusible fat and mineral substances in powder form.

7. A process for. protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat of liquid starch paste, whereupon the latter is dried and, before being thoroughly dry, sprinkled with stearin-powder.

I 8. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat of liquid starch paste, whereupon the latter is dried and, before being thoroughly dry, sprinkled with a mixture of stearin and talcum-powder.

9. A process for protecting stereotype matrices against the entering and adhering of metalduring the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat of collodin a vegetable paste preparation obtained from starch, whereupon the latter is dried and, before being thoroughly dry, sprinkled with an easily fusible fat in powder form.

10. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat of collodin, whereupon the latter is dried and, before being thoroughly dry, sprinkled with a mixture of easily fusible fat and mineral substances in powder form.

11. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat of. collodin, whereupon the latter is dried and, before being thoroughly dry, sprinkled with stearin powder.

12. A process for protecting stereotype matrices against the entering and adhering of metal during the casting-70f stereotype plates, consisting therein that the face of the the matrix is provided with a protecting of collodin, whereupon the latter is dried and, before being thoroughly dry, sprinkled with a mixture of stearinand talcum-powder.

13. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat, whereupon the latter is dried and, before being thoroughly dry, sprinkled with an easily fusible fat in powder. form, whereupon the matrix before placing same in the casting-apparatus is once more powdered with an easily fusible fat in powder form.

14. A process for protecting stereotype matrices against theentering and adhering of metal during the, casting of stereotype plates, consisting therein that the face of coat, whereupon the latter is dried and, before being thoroughly dry, sprinkled 'witl' an easily fusible fatin powder form, whereupon the matrix before placing same in the casting apparatus is once more powdered with an easily fusible fat and mineraksuo' stances in powder form.

.the matrix is provided with a protecting 15. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat, whereupon the latter is dried and, before being thoroughly dry, sprinkled with an easily fusible fat and mineral substances in powder form, whereupon the matrix before placing same in the casting apparatus is once more powdered with an easily fusible.

fat in powder form.

[6. A process for protecting stereotype matrices against the entering and adhering of metal during the casting of stereotype plates, consisting therein that the face of the matrix is provided with a protecting coat, whereupon the latter is dried and, before being thoroughly dry, sprinkled with an easily fusible fat and mineral substances in powder form, whereupon the matrix before placing same in the casting apparatus is once more powdered with an easily fusible fat and mineral substances in powder form.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

H U GO GO HN.

WVitnesses H Emir Hasrnn, VVoLnmun Haven 

